Offshore crude oil lease tank battery



Nov. 14, 1961 c. E. YOUNG, JR

OFFSHORE CRUDE OIL LEASE TANK BATTERY 2 Sheets-Sheet 1 Filed June 19,1958 INVENTOR. C.E. YOUNG .JR.

A TTOR/VE Y5 Nov. 14, 1961 C. E. YOUNG, JR

OFFSHORE CRUDE OIL LEASE TANK BATTERY Filed June 19, 1958 2 Sheets-Sheet2 C.E. YOUNG -JR.

A 7'TORNE VS Charles E. Young, Jr.,

3,008,599 OFFSHORE CRUDE OIL LEASE TANK BATTERY Houston, Tex., assignorto Phillips Petroleum Company, a corporation of Delaware Filed June 19,1958, Ser. No. 743,071 12 Claims. (Cl. 220-1) This invention relates toan oiishore tank battery for handlingcrude oil. In one aspect it relatesto an offshore tank battery for handling crudeoil wherein the entireplatform area is available for the auxiliary crude oil handling andprocessing equipment. In another aspect it relates to an offshore tankbattery system in which the treated crude oil storage'tanks are disposedbelow the working platform.

Offshore tank batteries are ordinarily placed upon a working platformwhichgin turn, is supported on piling driven into the ocean'floor. Sincesuch tank battery systems are intended to handle crude oil from a numberof wells, the storage tanks ordinarily are quite large.

3,0fl8,599 Patented Nov. 14, 1961 of the piling 17 is nearly flush withthe top of the surrounding guide pipe 12. Then another section of pilingis positioned on top of the driven piling and welded thereto to providean elongated piling member. The elongated piling is driven further intothe ocean floor. This operation is continued until each piling 17 is ofthe proper length. By this mode of assembly it is realized that eachpiling is accurately located or positioned. The piling 17 is driven intothe ocean floor to such an extent that the tops of the several pilingsare in a horizontal plane, or the upper ends are trimmed so that thetops of the several piling are disposed in a horizontal plane, a shortdistance below the level at which the tanks 18, 19, and are to bepositioned.

According to my invention the storage tanks, upper piling sections andflooring are assembled as a unit on land and the unit is floated tolocation and then raised The'tanks must hold considerable volume of oilbecause,

in many cases, the crude oil is transferred to shore in tank barges andthe battery tanks should be sufiiciently large to hold, for example,several days production from the several wells. It is desirable tocontinue normal oil production even during inclement weather whenordinary ship or barge transportation will not be possible.

According to my invention I provide an offshore tank battery platform onwhich is disposed treating tanks, settling tanks, pumping equipment,piping, and the like. In order that the entire platform surface will beavailable for such use, I have devised a storage tank assembly in whichthe tanks are supported beneath the working platform.

An object of my invention is to provide an offshore tank battery forhandling crude oil. I Another object of my invention is to provide anoffshore tank battery in which the entire platform area is available forthe oil treating and handling equipment.

Other objects and advantages of my invention will be realized uponreading thefollowing description which, taken with the attached drawing,forms a part of this specification.

In the drawing FIGURE 1 is a side elevational view of the completeassembly of my invention.

FIGURE 2 is an end view of the assembly of FIG- URE 1.

FIGURE 3 is a sectional view taken on the line 3-3 of FIGURE 1.

FIGURE 4 is a sectional view taken on the line 44 of FIGURE 1.

FIGURE 5 is a sectional view taken on the line 5-5 of FIGURE 3.

FIGURE 6 is a sectional view taken on the line 6-6 of FIGURE 4.

In the drawing reference numeral 11 identifies a template assembly whichcomprises vertical hollow cylinders or guide pipes 12 held rigidlytogether by horizontal cross members 13 and 15 and by diagonal crossmembers 14 and 16, as illustrated. In FIGURES 1 and 2 it is noted thatthere are 12. of these cylindrical guide pipes fastened together withthe above-mentioned braces. This template assembly is constructed onland by welding the various members together in the form illustrated andthe assembly is then transported by a ship or barge to the location atwhich the tank battery is to be constructed.

A crane then lowers the template to the floor 27 beneath compartment18?; from compartment 18a.

over the driven piling and the upper pilings 17a guided by spuds 17b-arepositioned on the upper ends of pilings 17 and welded thereto.

The upper piling joints or sections 17a are positioned through thebottom wall 32 (FIGS. 3 and 4) of the storage tanks 18, 19, and 2t?onshore. In the construction of this apparatus as much as possible isdone onshore. In the assembly as illustrated in FIGURE 1 each of thetanks 18, 19, and 20' comprises three storage compartments'. In tank 18the compartments are identified by reference numerals 18a, 18b, and 180.A pair of bulkheads 29 is provided within the tanks to divide them intothe three compartments. FIGURE 3 is a sectional view through tank 18looking in the direction of bulkhead 29 between tank compartments 18aand 18b. In this figure it is noted that top piling member 17a extendsup into tank 18 to nearly the top thereof. The pile member 17a is weldedto the tank at welds 38 in such a manner as to provide a fluid-tightjoint. Around the inner periphery of the tank 18 at bulkhead 29 isdisposed an angle iron 31 for reinforcing purposes. This angle ironextends from one side of pipe 17a upward and around the inner peripheryof the tank and terminates at the other side of pile member 17a. Thisangle iron is, of course, welded at both' ends to the piling pipe 17a. Asmall portion of the angle iron 31 is cut away at the top of pilingmember 17a so that the'angle iron can be welded securely to the top of acircular steel plate 39 which is in turn welded to the top of the pipe17a. Disposed horizontally at spaced intervals from top to bottom ofbulkhead 29 are T-beams 30a, 30b, and 300 which are welded at one end.to piling 17a and at the other end to the angle iron 31.

The upper piling pipes or sections of piling 17a are, in essence,support columns for supporting the storage tanks 18, 19, and 20.

Bulkhead 29 is composed of two parts, 29a and 29b.'

Each of these parts is nearly a half circle and each fits in a crosssection of the tank between the upper pile section 17a and the wall ofthe tank and the other part fits-on the opposite side of the pilingsection 17a.

Thus, the actual bulkhead assembly comprises a portion of the piling 17awithin the tank, bulkhead members 29a and 29b and the angle iron supportbeam 3 1. Also, these members are welded fiuidtight so as to isolate,for example, compartment 18c from compartment 18b and The circular lineof contact of the upper piling section 17a with the tank is sealed byweld 38 so as to be fluid tight. This weld also provides a support forthe lower portion of the tank. A' cross brace 49 is welded to the upperpile section 17a and extends across to another piling section.

17a. Webs 35 are welded in place between braces 49, 23 and the tank wall32, as illustrated, as additional supports. Disposed on top of theseveral tanks are a .Iplurali-ty of I-beams '24 each of which isdisposed at right angles or transverse to the axes of the tanks so thateach I-beam of this plurality of beams is supported by all of the tanks.As will be noted in FIGURE 3, a lower portion of the I-beams 24 is cutaway to accommodate the upper circular wall of each tank so as toprovide a relatively large bearing surface between the I-beams and thetanks. These I-beams are attached to the tanks by welds 52. As will benoted from FIGURE 2, diagonal braces 23 extend from each brace 49 beloweach tank to a point at the top of an adjacent tank. The lower ends ofthe diagonal braces are welded to the horizontal braces 49 while theupper ends of the diagonal braces are welded to the l-beams 24. Thecross braces between two tanks can cross each other in any mannerdesired; preferably, however, one of the braces is composed of two partsand these two parts are welded to opposite sides of the other diagonalbraces to provide a cross brace having the form of an X.

Disposed on top of the several I-beams 24 are a plurality of I-beams 25and at right angles thereto. Upon these upper I-beams 25 is disposed aworking platform upon which is installed the various items of equipmentordinarily used in such offshore crude oil gathering and treatingsystems. For example, on platform 26 are disposed a heater-treater oroil-water separator 56, a gas-oil separator system 41, a fresh watertank 42, and a crane 43. The gas-oil separating system comprises aplurality of separating tanks 44 which communicate by way of a manifoldpipe 45 to the various wells. A pipe 46 conducts separated oil from theseparating tanks to the storage tanks 18, 19, and 20. Manifold 54 isprovided for disposal of separated gas, while pipe 54a is for disposalof separated water.

Manifold 4'7 conducts oil from storage tanks 18, 19, and 20 to a pipe 48which is adapted to be connected to either a pipe line or to a barge fortransport of oil from this storage tank battery to shore installations.

FIGURE 4 is a sectional view, taken on the line 4-4 of FIGURE 1. Theform of tank support illustrated in FIGURE 4 is used in conjunction withthe supports as illustrated in FIGURE 3, the difference being that thereis not a bulkhead at the support as illustrated in FIGURE 4. In thisfigure the upper section of piling 17a extends through the bottom wallof tank 18 and this piling section terminates short of the upper wall ofthe tank. A T-beam extends around the inner periphery of tank 18 fromone side of the piling section 17a to the other side. The uppermostportion of this T-beam rests upon a plate 36 which, in turn, issupported by the upper end of the piling section 1701. Radial braces 33and 34 are provided as illustrated. These braces 33 and 34 are attachedby welding to plates 51 which, in turn, are welded to the T-beam 50.Weld 55 rigidly attaches the wall of the tanks in FIGURE 4 to the upperpile section 17a in a fluid-tight manner. In FIGURE 4 web plates 35 arewelded to the lower surface of the tanks and to the bracw 49 and braces23 as additional supports for the tanks.

The I-beams 24 which rest upon the tanks, as illustrated in FIGURE 4,also have cutaway portions for conforming to the upper circular surfaceof the tanks for provision of large bearing surfaces. Welds 53 rigidlyattach these I-beams 24 to the upper surfaces of the tanks.

FIGURES and 6 are sectional views taken on the lines 5-5 and 6-6 ofFIGURES 3 and 4, respectively. FIGURE 5 shows bulkhead section 29b withits horizontal T-beam braces 30a, 30b, and 300, and the angle iron 31which passes around the inner tank wall 32 and rests upon plate 39.

FIGURE 6 shows the I-beam 50 around the inner tank wall 32 and restingupon plate 36 which in turn is supported by piling member 17a. Theradial braces 33 and 34 are shown.

A fender system is provided in conjunction with the hereindisclosedplatform assembly for the protection of the platform assembly and theboats from damage resulting from impacts between the boats and thepiling during loading and unloading operations in high seas.

Such a protective fender system is illustrated in FIG- URES 1, 2, 3, and4. Cable support brackets 61 are welded or otherwise suitably firmlyattached to the ends of I-bearns 24. Eye bolts 62 are passed through thehorizontal web of these brackets with the eyes being below the brackets.Yoke and pin assemblies 64 attach the upper ends of bumper cables 65 tothe eye-bolts. Nuts 63 adjust the tension of the cables 65. The lowerends of cables 65 are held firmly by a structural assembly comprising atension member 66, a compression brace 67, and a short member 70. Member70 is welded to compression brace 67 and to a triangular web plate 68,which in turn is welded to the brace 67. A yoke and pin assemblyattaches the lower end of the cables to this lower structural assembly.As mentioned above, the tension of the cables 65 is adjusted by nuts 63.

The I-beams 24 which are disposed directly over the tank partitions orbulkheads 29 require bracing because the cables experience considerabletension as a boat bumps the bumper assembly. Brace 72 is a short sectionof a 10-inch diameter pipe. This brace is welded to the underside of thebeam 24- near the end to which the sup port brackets 61 are attached,and to the outer wall of the tank, as by welds 76. Within the tanks acompression brace should be provided so that brace 72 cannot injure thewall of the tank when cable 65 is loaded. A 10-inch pipe of the properlength is split lengthwise into sections, and these sections areidentified by reference numerals 7'7 and 78. Pipe section 78 is weldedat one end to the inner wall of the tank and at the other end to pilingsection 17a. The long sides of this pipe section are welded to thebulkhead section 29a.

Semicircular openings are cut into the webs of the T- beams 36a, 30b,and 300 so that the pipe section 77 can be welded to bulkhead section29a, to the tank wall and to the piling section 17a and to the T-beams.The outer radius of the pipe section 17a is shorter than the length ofthe webs of the T-beam braces 30a, 35b, and 30c, thus these T-beams fitover the pipe section 77. Thus T-beam braces are preferably welded tothe pipe section 77 for improving rigidity of the assembly.

In FIGURE 4 is illustrated bracing for 'I-beams 24 which are notdisposed directly over a bulkhead partition in the tanks. A length ofpipe 79 is welded to the underside of the I-beam 24 and to the outerwall surface of the tank. A plate 80 is preferably welded to the tankwall and then brace 79 attached to this plate.

The tanks 18 and 20 are provided with the braces for the bumper cablesupporting I-beams while tank 19 is not, obviously, provided with suchbraces.

A cable 65 with its upper and lower supports are provided at the ends ofall I-beams 24, making four such cables on each of the two long sides ofthe platform assembly.

A fender is provided on the side of the cables to which a boat or bargeapproaches. These fenders are horizontally disposed structures suspendedat the water line, i.e., they extend a short distance below and a shortdistance above the actual water line. The fenders are the structureswhich boats contact when docking or when tossed by rough seas. InFIGURES l and 2 the fenders 71 are illustrated as to structure and meansof support and level adjustment. The fenders are elongated memberscomprising three or more long members 73 attached to short cross braces74 as illustrated in FIGURE 1. These fenders are suspended byblock-and-tackle assemblies 75. The blocks of the assemblies aresupported by the outer I-beams 25 of the platform. The block-and-tackleallows adjustment of the fenders in respect to water level as tides riseor fall. The long members 73 are channel irons, or such structuralmembers as will resist bending, and may be covered with suitablecushioning material to prevent sharp contact between the boat and thefender.

One consideration in providing a boat bumper for such a platformstructure as herein disclosed is the proper dissipation of the kineticenergy of a moving vessel by the bumper rather than by simple impact onthe platform structure. The cables 65 are suspended from the brackets 61about feet in front of the piling 17 and guide pipe 12 and are attachedat the mud line to the brace assemblies as illustrated in FIGURE 2. Uponapplication of horizontal thrust in the direction of the platformsupport at about the midpoint vertically of the cable, the cable willdeflect from the vertical until the kinetic energy of the moving vesselis absorbed by the cables and the vessels motion is retarded. Thefender'is relatively rigid and tends to distribute the impact to all thebumper cables.

The fender system as herein described is usually provided only on thelong sides of the platform assembly. However, if desired, they may beprovided on only the short sides, or on all four sides.

Placing the oil storage tanks 18, 19, and 20 below the top ends of thepiling allows the platform surface 26 to be used for other purposes. Inother words, the storage tanks do not utilize a part of the veryvaluable working surface of the platform. In one instance three storagetanks were feet in diameter by 104 feet long. The

tanks were spaced on 30-foot centers and supported by four 30-inchdiameter steel pipe piles. Each tank was divided into threecompartments. The total storage capacity of the tanks was 17,500barrels. The template guide pipes 12 were 33 inches in diameter and theyextended down into the ocean floor about 8 feet and extendedapproximately 10 feet above mean sea level.

The separation-storage platform, as illustrated herein, is of a uniqueand novel design in that the horizontal storage tanks serve the dualpurpose of storing produced oil as well as acting as primary structuralmembers of the platform. It should be noted that there are no diagonalbraces from piling to piling which extend into a single tank because thetank walls themselves serve as very effective cross braces. However,diagonal braces are provided from the piling extending into one tank tothe corresponding piling extending into an adjacent tank.

While certain embodiments of the invention have been described forillustrative purposes, the invention obv-iously is not limited thereto.

Iclaim:

l. A fluid storage tank comprising, in combination, a tank of tubularform, the longitudinal axis of said tank being substantiallyhorizontally disposed, an upright support column extending fluid-tightthrough the lower wall of said tank and terminating short of the upperwall thereof, a tank wall reinforcing and support beam extending fromone side of said support column at it point of entry into said tankaround the inner periphery of said tank to the opposite side of saidsupport column, the upper portion of said support beam being attached tothe upper end of said support column and being supported thereby, and aninlet and outlet to said tank.

2. In combination with the fluid storage tank of claim 1, support bracesextending from the support column within said tank to said support beam.

3. A fluid storage tank supported by its upper and lower wallcomprising, in combination, an elongated tank of tubular form, thelongitudinal axis of said tank being substantially horizontallydisposed, a plurality of horizontally spaced upright support columnsextending through the lower wall of said tank along its axis andterminating short of the upper wall of said tank, a separate tank wallreinforcing and support beam extending from one side of each supportcolumn at their points of entry into said tank around the innerperiphery of said tank to the opposite side of said columns, the upperportion of the support beams being attached to the upper end of therespective support columns and being supported thereby, the upper andlower tank walls serving as bracing from one support column to anothersupport column of said plurality of support columns, and an inlet andoutlet to said tank.

4. A fluid storage tank battery system comprising, in combination, aplurality of elongated tubular tanks, the longitudinal axes of saidtanks being approximately horizontally disposed and mutually parallel, aplurality. of upright support columns extending fluid-tight andvertically through the lower wall and terminating short of the upperwallof each tank, a separate tank wall reinforcing and support beamextending from one side of each support column at its point of entryinto its tank around the inner periphery of the tank to the oppositeside of each support column, the upper portion of each support beambeing attached to the upper end of its support column and being.supported thereby, an inlet and outlet from each tank, a separatestructural beam supported on the top surfaces of said plurality of tanksdirectly above corresponding tank wall reinforcing and support beams,horizontally disposed cross members con- 7 necting corresponding supportcolumns of adjacent tanks, and separate diagonal braces connecting thestructural beams and corresponding cross members intermediate adjacenttanks.

5. In combination with the fluid storage tank battery of claim 4, aplurality of support braces extending from each support column withinthe tank to the corresponding support beam, and the tank walls providingbracing for adjacent support columns along the axis of each tank.

6. In the tank battery system of claim 4, a utility platform supportedby the top surfaces of said plurality of tanks, said platform comprisingin addition to the aforesaid structural beams resting upon said tanks,cross beams supported by and disposed transverse to said structuralbeams, and a working platform supported by said cross beams.

7. In the tank battery system of claim 6, a crude oil treating systemdisposed operatively on said platform, a conduit communicating saidtreating system with said tank battery, and an outlet for stored oilfrom said tank battery.

8. An offshore crude oil tank battery system comprising, in combination,a plurality of elongated cylindrical tanks, the longitudinal axes ofsaid tanks being approximately horizontal, mutually parallel anddisposed at about the same elevation, a plurality of tubular membersextending vertically through the lower wall of each of the tanks, saidtubular members being fixed fluid-tight to said wall of said tanks, eachtubular member of the plurality of tubular members extending into onetank of said plurality of tanks corresponding to a separate tubularmember of the plurality of tubular members extending into another andadjacent tank of said plurality of tanks, a first separate horizontalcross brace and support member supported by the upper wall of saidtanks, a second separate horizontal cross brace fixed to correspondingtubular members of adjacent tanks and therebelow, diagonal cross bracingmembers fixed at one end of each to each separate horizontal secondcross brace and at the other end of each to each separate firsthorizontal cross brace, and a platform supported by the first horizontalcross braces.

9. The system of claim 8 wherein said tubular members are the upper endsections of the piling disposed in the floor beneath a body of water andthe tank walls being bracing for adjacent tubular members parallel tothe axis of each tank.

10. An offshore storage tank and battery system comprising, incombination, a plurality of elongated tubular tanks, the longitudinalaxis of said tanks being substantially horizontal, mutually parallel andat about the same elevation, a plurality of vertically positionedtubular members spaced singly along the axis of each tank and extendingfluid-tight and vertically from below each tank through the lower Walland terminating near and supporting the upper wall thereof, each tubularmember of said plurality of tubular members extending into one tank ofsaid plurality of tanks corresponding to a tubular member of theplurality of tubular members extending into another and adjacent tank ofsaid plurality of tanks, a plurality of separate structural beamssupported on the top surfaces of said plurality of tanks abovecorresponding vertical tubular members, a plurality of separatehorizontal cross braces fixed to corresponding tubular members ofadjacent tanks and therebelow, and a separate diagonal cross brace fixedat one end of each to each horizontal cross brace and at the other endof each to a corresponding structural beam.

11. The system of claim 10, wherein said tubular members are the upperend sections of piling disposed in the floor beneath a body of water.

8 12. In the system of claim 11, a platform supported by said structuralbeams.

References Cited in the file of this patent UNITED STATES PATENTS OTHERREFERENCES Civil Engineering, July 1956, pp. 41-43.

